Curta collector's calculator

Relegated to collector's item since the arrival of electronic calculators, the curta calculating machine (die kleinste universal-rechenmaschine according to its manufacturer) was invented by curt herzstark during his imprisonment in the buchenwald concentration camp. After the second world war, he perfected the design and a prototype was produced by rheinmetallwerke in weimar, but it was the prince of liechtenstein who bought the concept. The machine was manufactured in vaduz (liechtenstein) by contina ag mauren between 1948 and 1972. This tiny, coffee grinder-like machine is a type I with the number 2835; it allows you to perform the 4 basic arithmetic operations very quickly and, after learning, other operations such as square roots. It was used by my father during his studies at arts and crafts in aix in provence in the 1950s. Comes without notice but many tutorials available online or notices to be acquired online.